Poplar tree are tall, narrow trees that are often used as windbreakers or property line markers. They also make outstanding companions to tall houses as landscaping trees. The poplar tree can grow over 70 feet tall, and has a branch span of 20 to 40 feet. Poplar trees require little care after initial planting, and grow several feet each year. In just a few years a short seedling will be transformed into a stately tree.
The poplar tree prefers a location in full to partial sunlight. They grow well in U.S. hardiness zones 4 to 9, and have tolerable drought tolerance. They are also adaptable to freezing temperatures in the winter. The tree prefers dryer temperature, but can also grow in more humid climates.
The ideal soil for poplar growth is rich soil that can retain moisture. The growth site should not be placed on a sloped area. The organic matter (such as leaves, manure and other composts) should equal about 8 percent of the soil surrounding the tree. The ideal soil pH for the poplar tree is 5.5 to 7.8. The tree should not be placed in highly alkaline soils as this can kill the plant. After planting place a 1 inch layer of mulch around the tree base.
The poplar tree needs frequent watering. The ideal placement for poplar tree is where the water table is 1.5 to 3 feet below the surface of the soil. If the water table is below this, then frequent watering will be necessary. Ensure the plant receives 1 to 3 inches of water per week, whether from watering or rain fall. A rain gauge installed near the tree can help determine how much water has fallen.
The poplar tree thrives with frequent fertilization. Use a slow release fertilizer with a 10-10-10 mix. In the spring, until the end of May, fertilize the tree twice a month. During the summer fertilize the tree once a month. Do not fertilize after October. Do not allow the fertilizer to touch the trunk of the tree. Fertilize a 10-by-10 foot area around the tree.
In general, poplars do not need much pruning. However, occasionally the tree will need pruning if it spreads wider than expected or when branches die out. Prune during the summer or early fall before the tree goes into dormancy for the winter. Prune away any dead branches, and prune any branches that detract from the long narrow shape that most poplars have.